As of this moment, the United States currently has over $9.4 trillion in "public debt" and an additional $4.65 trillion in "intragovernmental holdings". Combine the two amounts and you are left with the $14.05 trillion in "total public debt outstanding".

"Intragovernmental holdings" is money that the government has borrowed from itself. An example of "intragovernmental holdings"? The government borrowing money from the Social Security fund and then issuing an IOU to itself. This is what the term "intragovernmental holdings" means.

Net interest calculations don't include "intragovernmental holdings", as the government is just paying interest to itself, which results in "transactions that have no effect on net interest or the budget deficit".

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Anyways, now that we have explained that, let's take a look at the CBO's projections for outlays of net interest over the next decade in the country.

As mentioned, in 2010, outlays for net interest in the United States totaled $197 billion. For each dollar in revenues that the United States collected in 2010, 4.6 cents went to pay for interest on the national debt.

In regards to net interest, the country is expected to suffer from a double-whammy over the next ten years.

To start, the CBO projects that the debt that is held by the public will soar from $9 trillion to $18 trillion by the end of 2021.

In addition, the CBO also estimates that interest rates will rise substantially by 2021, which will also help to dramatically increase the cost of servicing the US debt load. Specifically, the CBO estimates that the interest rate on 3-month Treasury bills will rise from 0.25% in 2011 to 4.4% in 2021, and that the rate on 10-year Treasury notes will rise from 3.2% to 5.4%.

A soaring public debt load and rising interest rates? Not a good combination.

Let's look at the CBO's baseline projections of federal interest outlays from 2011 to 2021:

So, by 2021, the CBO estimates that the United States will be shelling out $792 billion per year in total net interest outlays. That's a 302% increase from the amount that the United States paid out in 2010.

From 2012-2021, the CBO estimates that the United States will pay out $5.45 TRILLION in total net interest outlays.